[FPSPACE] Dual Orion capsules studied for manned asteroid missions

[Michael K. Heney]

Take a look at J002E3 - initially thought to be a NEO when discovered in 
September 2002, it turned out to be the S-IVB from Apollo 12.  The stage 
entered a heliocentric orbit after sending Apollo 12 on its way to the 
moon; in 2002, it was recaptured into a chaotic orbit as it passed near 
the Earth-Sun L1 point; it was ejected back into heliocentric orbit in 
July 2003, and may do it again sometime in the 2030-2040 timeframe...

So, nudging Apophis (an exercise left to the reader...) to interact with 
the L1 (or L2 point) for capture into an unstable orbit, and then tweaking 
that orbit to something more stable would do the trick.

Of course, there IS a wee difference in situations (ignoring mass) ... 
The S-IVB is in an earth-grazing orbit - with an eccentricity only 
slightly different than Earth's.  It approaches gently, on a tangent to 
the L-1 point.  Apophis is an Earth-crossing asteroid, with an 
eccentricity of about .19 - it's movin' on through as it approaches Earth. 
You'd want to bump it's aphelion down from 1.1 AU to closer to 1, raise 
the perihelion from .75 to something much closer to 1, and do it in such a 
way so that it still ends up near the Earth so it can be captured.

That's a lot of noodging on a good-sized (350m) rock ...


On Fri, 21 Aug 2009, David R. Woods wrote:

> Jens,
> 
> Do you know of any references that describe how that capture process could take place? 
> Typically, with conservation of momentum, there is too much energy for something to be captured
> if it comes in from beyond Earth's gravitational well.  I could see a sling shot maneuver using
> the Moon to somehow put it into a retrograde orbit, but that seems bazaar and dangerous if you
> did not get it exactly right.
> 
> Dave
> 
> -------- Original Message --------
> Subject:
> Re: [FPSPACE] Dual Orion capsules studied for manned asteroid missions
> Date:
> Fri, 21 Aug 2009 21:58:17 +0200
> From:
> Jens Kieffer-Olsen <dstdba at post4.tele.dk>
> Reply-To:
> dstdba at post4.tele.dk
> Organization:
> Indian Red
> To:
> <fpspace at friends-partners.org>
> 
> <snip>
> 
> Only by knowing the precise orbit of Apophis
> can the necessary combination of nudges and slingshots be calculated that will eventually
> deliver the asteroid into GEO.
>  
> <snip>  
> Jens Kieffer-Olsen
> Slagelse, Denmark
> 
>